About 20 Republican members of the Electoral College are considering voting against Donald Trump when they meet next week, according to Larry Lessig, a Harvard University constitutional law expert, Politico reports.

Lessig, who made a brief run for the 2016 Democratic presidential nomination, has been offering free legal advice to GOP presidential electors, who are giving thought to going against Trump, according to the website.

The Electoral College meets Dec. 19 to select the next president.

Politico notes that if all 306 Republican electors support Trump, he would easily clear the 270-votes needed to become president. But anti-Trump activists are pushing hard to convince 37 Republican to go against him.

"Obviously, whether an elector ultimately votes his or her conscience will depend in part upon whether there are enough doing the same," Lessig said. "We now believe there are more than half the number needed to change the result seriously considering making that vote."

His comments, however, fly in the face of assertions from Republican National Committee sources who say they found only one elector would defy Trump, Politico reports.

Only Chris Suprun of Texas has publicly declared his intention to cast his vote for someone other than Trump, Politico said.

Lessig did not release any information to back up his claim about the 20 Republican electors. Politico noted there hasn't been more than one "faithless" elector since 1832, when two Maryland electors abstained.

And the Hill notes scattered anti-Trump groups are "using every means at their disposal – lawsuits, petitions, and public and private pressure" to convince GOP electors to vote against Trump.

However, the website noted, the results of the presidential election are not expected to change.

About 20 Republican members of the Electoral College are considering voting against Donald Trump when they meet next week, according to Larry Lessig, a Harvard University constitutional law expert, Politico reports.